Map @ref(fig:currencymap) shows currency exchange rates from national currencies to US Dollar. Data is retrieved by means of Alpha Ventage API in real-time at foreign exchange opening hours.
Alpha Ventage API provides free API service for up to 5 API requests
per minute and 500 requests per day. To make sure that this limit is not
exceeded, the request frequency is set to 1 request per 20 seconds. >
Currently, the code retrieves data for the first country in the list of
alphabetically order countries, i.e. exchange rate of Afghan Afghani to
USD. > > You may retrieve exange rates of a larger number of
countries (see variabe numcalls <- 1). Keep in mind that
rendering time will increase with ~numcalls * 20sec.
A depreciation of a currency makes imports more expensive and leads to a demand shift away from foreign goods towards domestic goods (Towbin and Weber 2013). Conversely, strong currencies make imports more attractive.